<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    .top {
        margin: 10px auto;
        width: 1200px;
        /* height: 300px; */
        background-color: pink;
    }
    
    .left {
        float: left;
        width: 200px;
        height: 300px;
        background-color: skyblue;
    }
    .right {
        float: right;
        width: 950px;
        height: 300px;
        background-color: orange;
    }
    .bottom {
        height: 100px;
        background-color: brown;
    }

    .clearfix {
        clear: both;
    }
</style>
<body>
    <div class="top">
        <div class="left"></div>
        <div class="right"></div>
        <div class="clearfix"></div>
    </div>   
    <div class="bottom"></div>
</body>
</html>